Using a simplified transmission and reception technique to indicate wake up related information to a receiver in order to save power has been of interest for years. A low power energy detection based receiver operates to detect a wakeup code or pattern of bits and wakes up the remainder of the device in case of successful detection of the wakeup code or pattern of bits. Thus, the entire device or chip doesn't need to be awake all the time in order to receive a packet that is transmitted to it. Instead it goes to sleep with only the wake up receiver portion of the chip (which is very low power) running. This portion of the receiver constantly monitors for the presence of its pattern of incoming bits. A transmitter that wishes to communicate with this node first transmits a wake up bit pattern (wakeup code) known to both transmitter and receiver to wake up the receiving node. Subsequently, after wakeup, the transmitter communicates using the normal protocol, for example any of the wireless standards according to IEEE Standard 802.11 WiFi, or Bluetooth. In such a system it is possible that an adversary intent on discharging the battery for the node to frequently transmit a wake up pattern pertaining to a receiver in order to cause unnecessary wake ups and thereby drain its battery (known as a “power draining attack”). It is also possible to achieve this by pre-sharing a wakeup code that is unique to each device and never changes, where the pre-sharing medium is secure or unknown to the adversary. But due to the large number of devices, the number of such wakeup codes would be huge and hence their lengths also have to be high. This causes power consumption to go up which is highly undesirable and hence is not a viable solution.
Hence there is a need for avoiding a power draining attack, and to preserve battery life even in presence of an adversarial attack. In another scenario, it is desired to keep information on which devices are being woken up separate from elements that are not part of the network or other nodes of the same network.
In order to overcome the problems of the existing technology, the present inventor has developed a method and system of secure wakeup in a communication system such that unnecessary wake ups are reduced and the battery draining attack problem is reduced by an adversary device or a third party. In addition, the information of when and which nodes are being awakened remains secure.